Mobile communication systems have been developed to provide communication services to users while they are moving. With the rapid development of communication technology, mobile communication systems have provided rapid data communication services as well as voice communication services.
The specification for Long Term Evolution (LTE), one of the next generation mobile communication systems, is being standardized by the 3rd Generation Partnership Project (3GPP). LTE refers to a technology that can provide packet-based communication with a higher transmission rate of maximum 100 Mbps than the current data transmission rate. The standardization for LTE is almost completed.
It is very important to reduce the power consumption in wireless mobile communication systems. To this end, LTE mobile communication systems have employed discontinuous reception (DRX), so that UE devices transmit reverse-control signals only during the Active Time of a DRX cycle, thereby minimizing their power consumption.
New definition for operations of UE devices is required for their maximum process performance during the DRX.